Parasitic Arthropods of Sympatric Meadow Voles and White-Footed Mice at Fort Detrick, Maryland

Twelve species of parasitic arthropods (one sucking louse, two fleas, one tick, and eight mites) were recovered from 51 meadow voles, Microtus pennsylvanicus (Ord); whereas nine species (one sucking louse, one bot, three fleas, one tick, and three mites) were collected from 48 white-footed mice, Peromyscus leucopus (Rafinesque), live-trapped on the grounds of Fort Detrick, Frederick County, MD., during 1990 and 1991. The most commonly collected arthropods from M. pennsylvanicus were the fur mite, Listrophorus mexicanus Fain (approximately 2,720 specimens); the tropical rat mite, Ornithonyssus bacoti (Hirst) (987); the laelapid mites, Laelaps kochi Oudemans (733) and Androlaelaps fahrenholzi (Berlese (322); the sucking louse, Hoplopleura acanthopus (Burmeister) (121); the tick, Dermacentor variabilis (Say) (47); and the chigger mite, Neotrombicula whartoni (Ewing) (45). Arthropod densities were lower on P. leucopus, from which the most frequently recorded species were the sucking louse, Hoplopleura hesperomydis (Osborn) (98 specimens); the fleas, Epitedia wenmanni (Rothschild) (85) and Orchopeas leucopus (Baker) (61); and the mite, A. fahrenholzi (83). Although six species of arthropods parasitized both species of rodents, only two of these, A. fahrenholzi and D. variabilis, were relatively common on both hosts. Therefore, although the habitats of both host species partially overlap, their associated parasitic arthropods remain principally host specific. The potential significance of these findings with respect to vector-borne disease transmission is discussed.